Conventional RTOS processor has an embedded RAM in a microprocessor on a target board to enhance the speed of processing OS (operating system). However, RAM of a small size has been used in the RTOS processor due to the cost and some problems relating to designing of the processor.
Accordingly, in most systems, RAM is mounted outside so that stacks for a user mode having a comparatively large size of stacks can be mounted on the outside RAM, while interrupt vector tables and stacks of a system mode which influence relatively more on the speed of the system are allocated on the embedded RAM.
However, in the method having such a randomly fixed memory structure as described above, there is a problem that the speed of the system is slow.